Mark, I bought my pair of 1960 era quads in Piney Flats, TN, which is not too far from you. I drive them with either a Mac MC240 or a pair of Klimo Kent amps. When I bought the speakers they were arcing during the audition. Using numerous online postings as my guide, I replaced the arced treble panel with one I bought at auction and had shipped from England for about $80, upgraded the power supplies with new parts, added clamp boards (also purchased from England) for protection and replaced the dust shields. The process of fixing them was not hard and did not cost much money and since you have the skills to build an amp and a preamp, I doubt you will have any problems with repairing a pair. From what I have read, the treble panels are usually the panels that arc so I would guess that most used pairs would have good base panels. If I was hunting for another pair, I would find a pair of original, unmolested, speakers and fix them. There is a very large price gap for a pair that have been refurbished and a pair that someone found at an estate sale.
The outfit that I bought the new parts from also sold new or rebuilt panels (I don't remember which) and he suggested that the his panels would not sound as good (or maybe it was the "same") as a good working original panel. I am not sure about that as those who have had their Quads rebuilt report that they are often significantly better than original. However, I do love the way mine sound and would not trade them for anything else I have heard.
Good luck.
The outfit that I bought the new parts from also sold new or rebuilt panels (I don't remember which) and he suggested that the his panels would not sound as good (or maybe it was the "same") as a good working original panel. I am not sure about that as those who have had their Quads rebuilt report that they are often significantly better than original. However, I do love the way mine sound and would not trade them for anything else I have heard.
Good luck.